I'd like an explicit formula as a function of $W_t$ (standard Brownian motion) and $\lambda >0$ for the solution of the following SDE:
$$\mathrm dX_t = \mathrm dW_t – \lambda X_t \,\mathrm dt$$
Someone could help me please?
probabilitystochastic-calculusstochastic-differential-equationsstochastic-integralsstochastic-processes
I'd like an explicit formula as a function of $W_t$ (standard Brownian motion) and $\lambda >0$ for the solution of the following SDE:
$$\mathrm dX_t = \mathrm dW_t – \lambda X_t \,\mathrm dt$$
Someone could help me please?
Best Answer
Since the given SDE is a linear SDE we can solve this equation using a similar approach as for linear ODEs:
Using this approach one can solve any linear SDE of the form
$$dX_t = (\alpha(t)+\beta(t) \cdot X_t) \, dB_t + (\gamma(t) + \delta(t) \cdot X_t) \, dt$$
where $\alpha,\beta,\gamma,\delta: [0,\infty) \to \mathbb{R}$ are determinstic coefficients.